Horizontal drawing press



ug. 25, 1970 E. NACKE Homzonm. DRAWING PRESS Filed March 11, 1968 7 Sheets-Sheet l @si t x9- :KIUATTORNEY ug- 25 1970 E.NAcKE HORIZONTAL DRAWING' PRESS 'T Sheets-Sheet 2 Filed March 1.1, 1968 lNvENToR [llc/f NAC/( ikNALI'TORNEY A E. NAcKE HORIZONTAL DRAWING PRESS 7 Sheets-Sheet 3 Filed March l1, 1968 INVENTOR [RM/f /VA 6K5 BY ss {Krl ma ATTORNEY Aug 25 `w70 E. NACKE 3,525,246

HORIZONTAL DRAWING PRESS Filed March 11, 1968 7 Sheets-Sheet 4 FIG. 4

ATTORNEY Aug. 25, 1970 v E, NACKE; 3,525,246

HORIZONTAL DRAWING PRESS Filed March l1, 1968 7 Sheets-Sheet 5 ATTORNEY ug. 25, 1 970 v E. NACKE 3,525,246

HORIZONTAL DRAWING PRESS Filed March 11, 1968 '7 Sheets-Sheet 6 BY WA g. R055 ATTORNEY Aug. 25, 1910 E. NAcKE HORIZONTAL DRAWING PRESS Filed March 11, 1968 I '7 Sheets-Sheet '7 INVENTOR VQ/H IVA CKE ATTORNEY United States Patent Cflce 3,525,246 Patented Aug. 25, 1970 3,525,246 HORIZONTAL DRAWING PRESS Erich Nacke, Sevelen, Germany, assgnor to G. Siempelkamp & Co., Krefeld, Germany, a corporation of Gerany Filed Mar. 11, 1968, Ser. No. 712,055 Claims priority, application Germany, Mar. 10, 1967, S 108,735; Apr. 13, 1967, S 109,304 Int. Cl. B21c 1/24 U.S. Cl. 72-283 10 Claims ABSTRACT F THE DISCLOSURE assembly locked in position, this retraction may be car? ried out with the aid of a set of pinions or sprockets or a crosshead of that assembly and co-operating rack teeth or chain links on a coupling bar rigid with the mandrel support.

My present invention relates to a drawing press for the production of seamless tubing and, more particularly, to a press of this type in which one of two co-acting shaping tools, usually a mandrel, is horizontally reciprocated by fluid-operated drive means with reference to the other tool, usually a drawing ring.

In conventional presses of this description in which a blank to be drawn is placed hot on the mandrel in a retracted position of the latter, the press frame must be Well over twice as long as the mandrel to allow for a separation of the retracted mandrel from the drawing ring suflicient to accommodate the new blank. To avoid this inconvenience, some drawing presses are made with their mandrel supports laterally swingable for loading purposes; this, however, requires additional space in the transverse dimension of the apparatus.

The general object of my invention is to provide means in such drawing press for facilitating the loading thereof without the need for an extra pathway for the reciprocable tool support or for a swingable mounting of the mandrel.

Another object of this invention is to provide a stable, jamproof and convenient arrangement for loading and operating such a drawing press.

These objects are realized, pursuant to my present invention, by the provision of a detachable coupling between the movable tool support and a structure which is axially reciprocable by the fluid-operated drive means whereby, in ya retracted position of that structure, this support can be further withdrawn to separate the two co-acting tools from each other to the extent required for tting a new blank to the mandrel. When this is done, the movable support is again thrust forward until the blank contacts, or nearly contacts the draqwing ring, whereupon the reciprocable structure may be re-engaged and the fluid-operated drive means may be restarted for another drawing operation.

In order to alord the necessary clearance for the additional withdrawal of the detached tool support, and to obtain a particularly stable construction not liable to canting, I prefer to design the fluid-operated drive means as a pair of piston-and-cylinder assemblies flanking the path of the reciprocable tool support. More specifically, this reciprocable support may be provided with a crosshead slidably guided on a pair of rails extending longitudinally of the press frame, another crosshead rigidly interlinking the movable members of the piston-and-cylinder assemblies (preferably the cylinders) so that the two crossheads move in unison when the movable tool support is coupled to its drive. Since the two crossheads will 'usually be axially separated by a considerable distance, the coupling mechanism may include a bar or other elongate member rigid wtih one of the crossheads and engageable with a latching device on the other crosshead; advantageously, the elongate member may be provided for this purpose with a plurality of axially spaced apertures or equivalent coupling formations engageable by the latching device in different relative positions of the'two heads.

According to another important feature of this invention, the final withdrawal of the movable tool support is carried out with the aid of an auxiliary driving mechanism adapted to displace this tool support relatively to the arrested reciprocable structure. Thus, the aforementioned elongate member may be provided with traction means, e.g. a series of surface formations such as a set of rack teeth or chain links, engageable by the teeth of a co-acting gear or sprocket wheel on the other crosshead.

In general, and as described in detail hereinafter, the tool caried on the movable support will be the mandrel; it'will be apparent, however, that the reverse arrangement, with the mandrel held stationary and the drawing ring being reciprocated, can also be used in a press according to the invention.

The above and other features of my present invention will become more fully apparent from the following description, reference being made to the accompanying drawing in which:

FIG. l is a plan view of a drawing press according to my invention;

FIGS. 2, 3 and 4 are cross-sectional views taken on lines lI-I-I, III-III and IV-IV, respectively, of FIG. l;

FIG. 5 is a plan view similar to FIG. l, showing a different embodiment;

FIG. 6 is a side-elevational view of the drawing press shown in FIG. 5; and

FIGS. 7 and 8 are cross-sectional views taken on lines VII-VII and VIII-VIII, respectively, of FIG. 5.

The drawing press shown in FIGS. 1-4 comprises a frame 1 forming a horizontal bed of generally rectangular configuration. Rigid with this frame is a xed tool support 2 adapted to receive drawing rings 3 of different sizes; a co-operating mandrel 6 is carried on an axially reciprocable tool support designed as a crosshead 4 so that a hot workpiece R, i.e. a blanky to be shaped by the tools 3 and 6, can be introduced by the mandrel into the drawing ring for thinning and stretching; it will be understood that, as long as the workpiece is hot, drawing rings of progressively smaller diameter may be mounted in cascade (as illustrated in FIG. 5), and that conventional means not shown may be provided for stripping the shaped workpiece off the mandrel during retraction thereof from the drawing ring last engaged thereby. To reciprocate the movable tool support 4 in this manner, I provide a pair of piston-and-cylinder assemblies 5a, 5b whose pistons 43a, 43b are rigid with a bridge piece 14 fixed to the press frame 1; the associated cylinders 12a, 12b, slidable along these pistons under hydraulic pressure, are secured to a crosshead 44 normally trailing the crosshead 4 by a distance D. Cylinders 12a, 12b carry respective webs 9a, 9b which are straddled by brackets 4a, 4b of the movable tool support 4; these brackets are formed with holes 8a, 8b which, upon being aligned with respective apertures 45a, 45b in webs 9a, 9b, give passage to latching bolts 7a, 7b carried on the ends of laterally movable pistons 10a, 10b of a hydraulically or pneumatically actuatable locking cylinder. It will be noted thatthe arrangement just described is duplicated both above and below the main driving cylinders 12a, 12b. Advantageously, each web or rod 9a, 9b is provided with a plurality of longitudinally spaced apertures 45a, 45b so that the distance D may be varied by locking the support 4 to these webs in different relative positions.

Tie rods 46a, 46b secured to cross-head 44 are slidable in tubes 47a, 47b rigid with the machine frame 1. Other cylinders 48a, 48b fixed to the frame, accommodate pistons 49a, 49b secured to crosshead 44. Thus, the movable structure 44, 12a, 12b, 49a, 49b is driven to the right (FIG. l), i.e. in a forward direction, upon admission of hydraulic uid into cylinders 12a, 12b and is driven to the left, i.e. retracted, upon the introduction of fluid into cylinders, 48a, 48b.

When, in the retracted position of the movable structure shown in FIG. l, the coupling device 10 is operated to withdraw the latch bolts 7a, 7b from the engaged holes 45a, 45h of webs 9a, 9b, the decoupled tool support 4 with its mandrel 6 may be moved further to the left, to the extent represented by distance D, so as to provide enough spacing between the mandrel 6 and the 4ring support 2 to allow for the insertion of a new blank R. This displacement of crosshead 4 independently of drive means a, Sb may be carried out by any suitable mechanism not shown; an advantageous arrangement for this purpose will be described hereinafter, with reference to FIGS. ,5-8.

The embodiment illustrated in FIGS. 5-8 comprises a press frame 15, generally similar to frame 1 of the preceding figures, carrying a fixed support 16 for a drawing ring 18 and another such support 17 holding a second, smaller ring 19. A mandrel 22, carrying the workpiece R, is again reciprocable (as indicated by arrow 23) along the common axis of rings 18 and 19. This axial reciprocation, under hydraulic pressure, is brought about by a pair of drive assemblies 21a, 2lb generally similar to the assembly 5a, 5b of the preceding embodiment; the corresponding cylinders, rigid with a crosshead 27, are shown at 41a, 41b. Another crosshead 20, representing the movable support for mandrel 22, is reciprocable jointly with crosshead 27 on a pair of rails 26a, 26h extending longitudinally of the frame 15. To couple the two crossheads together, head 20 has secured to it axially extending bar 24 `with a plurality of longitudinally spaced apertures 25 engageable by a vertically moving latching bolt 28 on crosshead 27. The upward withdrawal of latching bolt 28 into its disengaged position, illustrated in phantom lines in FIG. 7, is effected by a pair of hydraulic or pneumatic cylinders 33a, 33b with pistons 34a, 34b which are joined to a cross-bar 35 rigid with bolt 28. Again, as in the embodiment of FIGS. 1-4, the distance between the two crossheads is variable through the choice of different apertures 25.

Crosshead 27 also carries a pair of synchronously operable electric drive motors 29a, 29b for relatively displacing the mandrel support 20 and the driving head 27 thereof upon the decoupling of these elements from each other. Bar 24 is designed, for this purpose, as an I-beam with an upper and a lower flange 30, 31 and with lateral Webs 32a, 32b bearing traction formations, such as rack teeth, 36a, 36b in mesh with respective pinions 38 (only one shown) driven by motors 29a, 29b through speed reducers 37. A fixed bridge piece 39, similar to member 14 of FIG. 1, has the pistons 40a, 40b of hydraulic assemblies 21a, 2lb anchored to it; tie rods 50a, 50b,

4 movable in fixed tubes 51a, 51b, and hydraulically operated reverse drives 42a, 42b, similar to the assemblies 48a, 49a and 48b, 49b of the preceding embodiment, complete the actuating system.

The operation of the machine shown in FIGS. 5-8 is analogous to that described in connection with FIGS. 1 4. It will be noted that, with either embodiment, the movable support and its drive means are symmetrically disposed with reference to the path of the mandrel so that eccentric moments are avoided. Naturally, the arrangement shown and described is susceptible of various modlfications without departing from the spirit and scope of my invention as defined in the appended claims.

I claim:

.1. A drawing press comprising a press frame; a pair of co-operating shaping tools disposed along an axis; fixed support means for one of said tools; horizontally movable support means on said press frame for the other of said tools; fluid-actuated drive means including an axially reciprocable structure for alternately advancing and retracting said movable support means with reference to said fixed support means; and coupling means detachably linking said movable support means With said structure, said movable support means being axially withdrawable from said fixed support means independently of said drive means upon disengagement from said structure in a retracted position of the latter.

2. A drawing press as defined in claim 1 wherein said drive means comprises a pair of piston-and-cylinder assemblies flanking the path of said other of said tools.

3. A drawing press as defined in claim 2 wherein said drive means includes at least one piston member and at least one cylinder member, one of said members being fixed to said press frame, the other of said members being slidable along said fixed member, said structure comprising a crosshead interconnecting the slidable members of said assemblies, and rail means on said press frame slidable supporting said crosshead and said movable support means.

4. A drawing press as defined in claim 3 wherein said coupling means comprises a pair of parallel apertured bars rigid with said crosshead and latch means on said movable support means between said bars, said latch means including a pair of laterally movable pins insertable into respective apertures of said bars.

5. A drawing press as defined in claim 3 wherein said coupling means comprises an apertured bar rigid with said movable support means and latch means on said crosshead including a bolt insertable into an aperture of said bar.

6. A drawing press as defined in claim 1, further comprising an auxiliary driving mechanism for displacing said movable support means with reference to said structure upon mutual disengagement thereof.

7. A drawing press as defined in claim 6 wherein said movable support means and said drive means are provided with respective crossheads slidable on said press frame, said coupling means including an axially extending elongate member on one of said crossheads and cooperating latch means on the other of said crossheads, said auxiliary driving mechanism including traction means on said elongate member and co-operating means on the other of said crossheads engageable with said traction means.

8. A drawing press as defined in claim 7 wherein said traction means comprises two sets of surface formations on opposite sides of said elongate member, said cooperating means including a pair of toothed wheels respectively meshing with said sets of formations.

9. A drawing press as defined in claim 7 wherein said press frame is provided with a pair of parallel rails slidable supporting said crossheads, said rails being symmetrically disposed with reference to said tools.

10. A drawing press as defined in claim 9 wherein said drive means comprises a pair of pistons fixed to said press frame substantially in line with said rails and a. pair of cylinders siidable along said pistons and xed to one of said crossheads.

References Cited UNITED STATES PATENTS 2,492,876 12/ 1949 Mcllyried 72--283 X 1,654,585 1/1928 Fulton 72-283 2*,234l863 l3/19-41 Heetkamp 72--283 6 FOREIGN PATENTS 7/ 1931 Great Britian. 6/ 1907 Great Britian.

CHARLES W. LANHAM, Primary Examiner.

ANDREW L. HAVIS, Assistant Examiner. 

